# 用户行为日志表结构
user_behavior = [
    ("user_id", "string", "用户ID"),
    ("item_id", "string", "商品ID"),
    ("category_id", "string", "品类ID"),
    ("behavior_type", "string", "行为类型: click, view, collect, add_cart, purchase"),
    ("behavior_time", "timestamp", "行为时间"),
    ("duration", "integer", "浏览时长(秒)"),
    ("page_depth", "integer", "浏览深度"),
    ("is_purchase", "boolean", "是否购买"),
    ("order_id", "string", "订单ID(如果有)"),
]